3D FEM BEM-HYBRID APPROACH FOR PLANAR LAYERED MEDIA/

A finite element method (FEM)/boundary element method (BEM)-hybrid app roach is presented which allows electromagnetic field calculations in planar layered media including three-dimensional inhomogeneous regions . The fields within the inhomogeneities are modeled by the FEM in term s of the electric field strength (E) over right arrow with edge elemen ts on tetrahedral meshes. Based on Huygens' principle the BEM is formu lated with equivalent electric and magnetic surface currents on a surf ace completely enclosing the inhomogeneous regions. Additionally, idea l conducting objects can be included into the BEM-model. The electric field integral equation (EFIE) for the BEM is formulated as a mixed po tential integral equation (MPIE). Applications of the method to field calculations in a microstrip resonator with finite metallization thick ness and to the coupling of a cylindrical dielectric resonator to a mi crostrip line are presented.